Apparatus for engraving reticules



0ct. 20, 1942.y J. o. BLUHM APPARATUS FOR ENGRAVING RETICULES Filed June 25. 1941 3 Sheets-She-eb l 4' INVENTOR USE h D Elluhm @m (r1 ATT RNEYS Oct. 20, 1942. J. o. BLUHM 2,299,075

APPARATUS FOR ENGRAVING RETICULES Filed June 25, 1941 3 Sheets-Sheet 2 'NrVL'ENlTOREl h' 451.2111 u my ATTO NEYS Oct. 20, 1942. .1.0. BLUHM 2,299,075

' APPARATUS FOR ENGRAVING RETICULES Filed June 25. 1941 3 Sheets-Sheet 5 www muuu muuu INVENT BY ATT NEYS Patented Oct. 20, 1942 2,299,075 APPARATUS FOR, ENGRAVING RETICULES Joseph O. Bluhm, Philadelphia, Pa. Application June 25, 1941, Serial No. 399,747

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 6 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to engraving machines in general, and in particular to a means for mounting and lowering the stylus and bearings therefor.

In the usual types of engraving machines, the stylus is carried on a unit providing for motion of the stylus in a vertical plane on a pivoted arm to engage and disengage the work. The pivot bearings of such units are subject to wear thus effecting the flnal result at the stylus point and requiring adjustment to compensate for the Wear.

This defect is remedied in the machine of the invention which provides a resilient mounting for the stylus affording a constant pressure on the pivot bearings and continuously and automatically compensating for wear in the bearings.

It is therefore an object of this invention to provide bearing mountings for the pivoted portions o engraving machines with self-adjusting features.

It is a further object of this invention to provide resilient bearing mountings for the pivoted parts of engraving machines.

It is a further object of this invention to provide a novel stylus lifting and lowering unit.

To these and other ends, the invention consists in the construction, arrangement and combination of elements described hereinafter and pointed out in the claims forming a part of this specification.

A practical embodiment of the invention is illustrated in the accompanying drawings wherein:

Figure l is a view in side elevation showing the stylus suspension unit and its lever system in solid lines and other portions of the engraving machine in broken lines.

Figure 2 is a broken enlarged View in side elevation of the stylus support.

Figure 3 is a top plan view of Figure 2 showing one portion of a gang stylus unit.

Figure 4 is a plan view of a portion of the transmitting structure of an engraving machine.

Figure 5 is a section taken on the line 5-5 of Figure 4, and

Figure 6 is a section taken on the line 6-6 of Figure 4.

Referring to the drawing by characters of reference, there is shown in Figure 1 the stylus unit mounted on the engraving machine, which is shown schematically. Table I, which holds the have, therefore, either been omitted from the drawing or indicated generally by broken lines.

An enlarged view of the stylus unit is shown in Figures 2 and 3. The stylus 'I is held at the end of a lever arm 8 pivoted as at 9 and the stylus is urged downward by gravity aided by a supplementary weight I0. Stylus lever 8 is controlled by another lever II pivoted as at I2 and urged downward by gravity aided by a weight I3.

Lever II has attached to its inner end a bar I4 for contacting the lever 8 or a series thereof. This contact is actually made by means of a position adjusting screw I5. When lever II is `raised, the adjusting screw I5 on the inner end `thereof contacts the inner end of stylus lever 8 and the stylus is raised, and when lever II is permitted to drop, the stylus lever will likewise drop to engraving position.

Control lever II is manipulated by means of a plunger rod I6 carrying a table-like head I'I, preferably of disk form. The plunger is urged upward by means of a surrounding spring I8 (Figure 1) acting on a collar I9 fixed to the plunger rod I 6. The spring I8 is housed in a cylindrical chamber 20 through which the plunger rod I 6 passes. Plunger rod IB is urged downward against the spring by pressure of the operator on a member 2| pivoted to the rod I6 at its lower extremity, and the stylus is thus brought to engraving position under its constant weight.

Stylus lever 8 is pivoted at 9 by means of conically pointed screws 22 threadedly carried, respectively, by a fixed upright 23 and a parallel upright comprising a rear fixed portion 24 and a front portion 25 pivoted about a pin 26 which is seated in a top plate 21 straddling the uprights 23 and 24 and screw-fastened thereto. Fastened to the side of upright 24 by a screw 28 is a flat spring 29 which engages the side of the pivoted upright 25 and thus holds the pivot points in contact at 9 under a constant pressure irrespective of wear. Furthermore, if the stylus should encounter a iiaw in the material being engraved, the spring mounting will permit it to yield and save it from injury. Obviously, the spring shown may be replaced by other types of resilient retainers, the leaf spring being but a preferred form.

Inserted in the under side of control lever Il is a pin or screw with a rounded head 29 for engagement with the head Il of plunger rod lli. The disk il oiiers a considerable area of contact for the head 29 to permit contact during extensive travel of the stylus unit in all directions of its plane of motion.

In Figure 4 is shown a portion of the transmission linkage. Figure 5 is a section of a detail of the linkage of Figure 4. Arms 3l), 3l are received within the openings 32, 33 of a doublyforked seat l which is adjustably secured to an arm 35 of the transmission system by means of screws S and/or pins 3l. Arms 3l), 3l and the central partition 33 of seat 34 have, xed bushings Sll with flared openings lil) to receive ball bearings Ill. Threaded bushings l2 and 43 are provided in the outer arms of the doubly-forked member 34. One of these bushings, 42, has a central bore lill containing a plunger l5 urged outwardly by a spring 46. The tension on spring i6 may be regulated by screwing in either or both of the bushings d2, 43. Lock nuts 41 are provided for the threaded bushings 42, 53. By these means the friction in the pivot bearings may be adjusted and wear will be automaticallyl compensated for.

Figure 6, a detail of another point of linkage from Figure 4 will be self-explanatory in View of the description of Figure 5, the only essential difference being that a single arm 68 is pivoted Within a singly-forked member 4l).

I claim:

l. In an engraving machine, a carriage and holding means for a stylus lever thereon comprising aligned and opposed pivot points to receive the stylus lever therebetween, at least one of said pivot points being resiliently mounted.

2. In an engraving machine, a carriage and holding means for a stylus lever thereon comprising aligned and opposed pivot points to receive a stylus lever therebetween, a pivoted arm mounting one of the pivot points for swinging motion toward the other point and resilient means for holding the pivoted arm and pivot point in stylus-lever-holding position.

3. In combination, a stylus lever for an engraving machine, and a. pivotal mounting therefor, said mounting comprising a carriage and aligned and opposed bearing members engaging the stylus lever, holding means for each of said bearing members iixed to the carriage, at least one of said holding means comprising a swingable arm pivoted to the carriage and swingable to and from the other of said holding means, and resilient means to urge said swingable arm toward the other of said holding means and thus hold said arm and its bearing member in styluslever-retaining position.

4. In an engraving machine comprising a stylus lifting and lowering unit freely movable as a whole in a horizontal plane, a plunger rod with a flat table atop and transverse to the rod and a control lever pivoted on said unit, swingable in a vertical plane and with a weighted end resting on said table, said table being of suiiicient extent to support the control lever in all possible positions of the same in the plane of the table, and resilient means to hold said plunger rod in a raised position against the weight of the lever arm.

5. In an engraving machine, a mounting for a stylus comprising a carriage, and opposed standards on said carriage for receiving a stylus therebetween for pivotal rotation about an axis between saidl standards, one of said standards being pivoted to said carriage at a point offset from said axis for swinging motion to and from the other of said standards, and resilient means on said carriage positioned to urge the pivoted standard toward the other of said standards.

6. In a mounting as in claim 5, opposed bearing means adjustably received in said standards respectively dening the line of saidaXis.

JOSEPH O. BLUHM. 

